This invention relates to a device for mounting electronic components, particularly multiple-pin integrated circuits, to circuit boards.
In the automatic mounting of multiple-pin electronic components, such as integrated circuits having 4 to 40 pins or contact legs, to circuit boards, insertion errors occur frequently. Such insertion errors occur, for example, when the contact pins of the electronic components are misaligned with the respective holes or openings in the circuit board. During a motion of the electronic component toward the circuit board in an insertion operation, the misaligned contact pins buckle upon contact with the surface of the circuit board. The undesirable result of the insertion errors is the existence of faulty connections in the electric circuit on the circuit board.
To check for the occurrence of insertion errors in the mounting of multiple-pin integrated circuit components to circuit boards, automatically assembled subassemblies have been conventionally subjected to a visual inspection after the insertion operation. The visual inspection is directed in particular to determining that the inserted terminal pins of each electronic component appear in pairs.
The visual inspection process has been facilitated by producing an image of the terminal pins on a piece of paper through the use of carbon paper and a rubber pressure roll. Furthermore, as described in commonly owned U.S. patent application Ser. No. 607,908, a device for mounting electronic components to circuit boards may be provided in the region of a support anvil with an optical monitoring device for detecting the ends of the terminal pins protruding from the circuit board on a side thereof opposite the electronic component.
An object of the present invention is to provide an improved mounting device of the above-described type which includes means for automatically monitoring the assembly process for the occurrence of insertion errors.
Another, more particular object of the present invention is to provide such a mounting device in which the automatic monitoring operation occurs during the assembly process.
Another, more particular, object of the present invention is to provide such an improved mounting device in which insertion errors can be detected for electronic components having two rows of at least two terminal pins each.